Process for the production of blue sulfur dyes.



Rmrlmmmum osoen unusual, or BASEL, svrirnnnitann. nssrou'on ro CHEMICALWonns, roiaiannnu' saunoa, or JBASJEL, svvrrnfunneun.

PRQGESS FOR, THE PRODUCTION 01? BLUE SULFUR IDYllfl.

No Drawing.

To all whom it may concern:

' vented a certain new and useful Improved Process for the ProductionofBlue Sulfur lDyes, of which the following his specification.

This invention relates to animproved process for the manufacture of bluesulfur d es. y

lit is well known, that certain alphyl-para amido;para-oxy-dialphylamidocompounds as Well as the corresponding indophenols when treated Withpolysulfids are transformed into blue sulfur dyes.

My invention is based on the discovery that the same parent-materials inmixture with paranitroamido-benzene compounds, containing no hydroxylicgroup, when treated with polysulfid under suitable conditions yield bluesulfur dyes, which are in general similar to the corresponding dyestuffsobtained Without the addition of a nitroamido compound,'but are superiorto them, both in fastness and purity of the shade as well as by theirintensity. Thus the presence of the paranitroamido compounds appear toavoid the formation of secondary products of a dull tint and withinferior coloring capacity.

Tn carrying out the invention, the following substances have been foundto give good results: the alphyl-p-amido-p-oxydiphenyl amines, thep-oxy-p-amido-m-alkyl-diphenylamins, thedi-alkyl-pam1do-p-oxydiphenylamins, the indophenols and their respective'reduction products, obtained by condensation of nitrosophenols withcarbazol or its. derivatives, and the like.

'Among the pnitro-amido-benzene com-- pounds, containing no hydroxylgroup, the following maybe employed with advantage: the p-nitro-anilin,the m-n1troo-tolu1- din on ;uii,=uo =1=2=5, the dichlorop-nitranilinNH,=o1=uo =o1=1;2:a;e, the p-nitrodimethylanilin, the p-n1tran1l1n-osulhonic acid NH :S@ l'l:l"l(l :-1:2:a, an other analogous substances.

Example I: 13.8 parts of the leucoindophenolphenyl-p-am1do-p'-onydiphenylam n and 8 parts of p-nitramlin aredissolved in a hot solution of polysulfid obtained from 6.6 parts ofsodium sullid 60/62%, 3.2 parts of sulfur and 100 parts of methylicorethylic alcohol. The solution after having Specification of LettersPatent.

Patented llllay 6, rain.

Application filed December M, 1918. llcrial No. 266,83l.

been filtered is heated for l8 hours under pressure (6 to-8 atmospheres)at a temperature of 120 to 125 centigrades; then the alcohol is drivenoff by distillation; the residue which is in the form of a liquid pasteis dissolved. in hot water, and the dye-- stud is isolated byprecipitating it by acetic acid or by blowing a current of air into thesolution. 1

After filtration, washing and drying, the dyestufi forms a deep bluepowder, having a cuprous luster. It is practically insoluble in Waterand alcohol. In strong sulphuric acid and in cold anilin and pyridin itdissolves with blue color. The dyestuff dissolves readily in a hotsolution of sodium sulfid, forming a leuco derivative; this solutiondyes unmordanted cotton at first in clear grayish green tints, which onexposure to the air, are rapidly developed into a bright indigo blue.

Example ll: 21% parts of the leucoindophenolp-oxy-pnmidoan-methyl-diphenylamin and 16 parts of p-nitranilin areadded to a solution of polysulfid formed by boiling 13.2 parts of sodiumsulfid /62% strength, 6.4 parts of sulfur and i0 parts of water. TheWater is driven off by distillation until the boiling point reaches108-110 C. andthen the solution is heated to that point on the refluxcondenser for 24: hours, stirring all the time in any suitable manner.The liquid paste thus obtained is dissolved in hot water and thedyestuff is isolated as described in Example l.

The thus produced. dyestuff forms a deep blue powder with a cuprousluster and is almost insoluble in Water and alcohol. Sulfuric acid andalso pyridin dissolve it With blue color, hot anilin with violet lcolor.

on addition of 141.5 parts of the leucoindophenol phenyl pamiddp-o2ry-m-1nethyldiphenylamin and 12 parts of dichloronitranilin NH,Cl N0 (ll-:1z2 :476, is heated under pressure (6 to 8 atmospheres) for48 hours at a temparture of 120425 C.

until'the formation of the dycstufl' is com pleted. The methylic alcoholhaving been distilled olf, the residue is dissolved in hot Water and amixture of the leueo derivative of the dyestuff and ofdichloro-p-phenylenediamin formed during the process is pre cipitated bycarefully neutralizing the solution by acetic acid. By repeatedextractions With diluted hot hydrochloric acid. the dyestufi' isobtained in form of a deep blue powder almost insoluble in'Water andalcohol. It dissolves in sulfuric acid, in anilin and in pyridin, givinga blue solution. In a bath containing sodium sulfid it dyes unmordantedcotton a clear brownish-gray which by exposure to the air is developedinto a reddish indigo blue.

It Will readily be understood by those acquainted With this art, thatsome of the de tails given .in the above examples may be variouslymodified Without departing from the scope of the invention, and withoutfundamentally altering the character of the dyestuffs produced. F orexample, variations may be made in the proportions of the substancesmentioned, in the temperature at which, or between which, the processshould be carried out, and in the precise nature of the solventsemployed; also the reaction,

especially as regards Example II may be carried out in a closedreceptacle.

What I claim is p 1. The herein described process for the production ofblue sulfur dyes which consists in treating a mixture ofleucoindophenols and of nonhydroxylated paranitroamido compounds of thebenzene series with polysulfids. I

2. The herein described process for the production of blue sulfur'dycswhich consists in treating a mixture of analphylparaamidoparaoxydialphylamido compound and a nonhydroxylatedparanitroamido compound of the benzene series with. polysulfid.

3. The herein described process for the production of a blue sulfur dye,which consists in treating a mixture of phcnyl-pamide-p-oxydiphcnylaminand p-nitranilin with polysulfids.

4. As a new article of manufacture the blue sulfur dyes prepared from amixture of a leucoindophenol and a non-hydroxylated paranitroamidocompound of the benzene series by treatment with polysulfids, whichdyestufi's form in dry state a blue powder, practically insoluble inWater and alcohol, dissolving in concentrated sulfuric acid, anilin, andpyridin, with blue color and dyeing unmordanted cotton from a bathcontaming sodium sulfid in bright indigo I shade In testimony whereof Ihave signed my name to this specification.

OSCAR KNECHT. Witnesses:

H. H. DICK, ldnnonron Bonmenn.

